Adaptive inductive power supply

• US 9,190,874 B2
• Filed: 04/01/2011
• Issued: 11/17/2015
• Est. Priority Date: 02/04/2003
• Status: Expired due to Term

• Current Assignee: Philips IP Ventures B.V. (Koninklijke Philips N.V.)
• Original Assignee: Access Business Group International LLC (Alticor Incorporated)
• Inventors: Baarman, David W.
• Primary Examiner(s): Han, Jessica
• Application Number:
  US13/078,094
• Publication Number:
  US 20110175458A1
• Time in Patent Office: 1,691 Days
• Field of Search: 363/16, 363/21.01, 363 39- 41, 363/97, 363/131, 324/429
• US Class Current: 1/1
• CPC Class Codes: A61L 2/10 Ultraviolet radiation
• CPC Class Codes: H02J 13/00022 using wireless data transmission
• CPC Class Codes: H02J 13/00024 by means of mobile telephony
• CPC Class Codes: H02J 13/00028 involving the use of Internet protocols
• CPC Class Codes: H02J 2310/22 The load being a portable electronic device
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02M 3/015 with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuit
• CPC Class Codes: H02M 3/33523 with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/33571 Half-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/33576 having at least one active switching element at the secondary side of an isolation transformer
• CPC Class Codes: H02M 7/4815 Resonant converters H02M7/4811 and H02M7/4826 take precedence
• CPC Class Codes: H02M 7/4818 with means for adaptation of resonance frequency, e.g. by modification of capacitance or inductance of resonance circuits
• CPC Class Codes: H02M 7/53803 with automatic control of output voltage or current
• CPC Class Codes: H05B 41/36 Controlling
• CPC Class Codes: H05B 47/20 Responsive to malfunctions or to light source life; for protection
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/246 the system involving the remote operation of lamps or lighting equipment

Abstract

A contactless power supply has a dynamically configurable tank circuit powered by an inverter. The contactless power supply is inductively coupled to one or more loads. The inverter is connected to a DC power source. When loads are added or removed from the system, the contactless power supply is capable of modifying the resonant frequency of the tank circuit, the inverter frequency, the inverter duty cycle or the rail voltage of the DC power source.

Claims

1. A contactless power supply for supplying power wirelessly to an electrically powered remote device comprising:

a tank circuit having a primary for transferring power to said electrically powered remote device by an inductive coupling, said electrically powered remote device having a secondary in electrical communication with a load, said tank circuit having a resonant frequency;

drive circuitry for applying power at a rail voltage to said tank circuit, said circuitry applying said power at an operating frequency and a duty cycle;

a controller coupled to said drive circuitry, said controller configured to actively vary said resonant frequency of said tank circuit; and

throttling circuitry coupled to said tank circuit, said throttling circuitry for throttling said power.

2. The contactless power supply of claim 1 wherein said controller is configured to actively vary, in addition to said resonant frequency, at least one of said operating frequency of said power, said duty cycle of said power and said rail voltage of said power.

3. The contactless power supply of claim 2 wherein said at least one of said operating frequency of said power, said duty cycle of said power and said rail voltage of said power is further defined as said operating frequency of said power and said rail voltage of said power.

4. The contactless power supply of claim 2 wherein said at least one of said operating frequency of said power, said duty cycle of said power and said rail voltage of said power is further defined as said operating frequency of said power and said duty cycle of said power.

5. The contactless power supply of claim 1 wherein said controller is configured to actively vary said resonant frequency of said tank circuit, said operating frequency of said power, said duty cycle of said power and said rail voltage of said power.

6. The contactless power supply of claim 1 further including a circuit sensor coupled to said tank circuit and to said controller, said circuit sensor providing said controller with an input indicative of a characteristic of power in said tank circuit;

and

wherein said controller is configured to actively vary said resonant frequency and at least one of said operating frequency of said power, said duty cycle of said power and said rail voltage of said power as a function of said input indicative of a characteristic of power in said resonant circuit.

7. The contactless power supply of claim 1, wherein said controller includes said throttling circuitry in a microcontroller adapted to perform digital signal processing.

8. The contactless power supply of claim 1, wherein said throttling circuitry is configured to insert a delay to throttle said power.

9. The contactless power supply of claim 8, wherein said delay is a phase delay that changes a secondary amplitude.

10. The contactless power supply of claim 8, wherein said throttling circuitry includes a digital signal processor for inserting said delay.

11. The contactless power supply of claim 1, wherein said throttling circuitry is configured to throttle said power by throttling a phase, and wherein said throttling a phase affects a secondary amplitude.

12. A method of operating an inductive power supply for an electrically powered remote device, the method including the steps of:

applying power to a tank circuit within the inductive power supply;

establishing an inductive coupling between the inductive power supply and the electrically powered remote device, wherein the electrically powered remote device has a secondary in electrical communication with a load;

monitoring at least one operating parameter of the inductive power supply after establishing the inductive coupling;

based upon said monitoring step, configuring the inductive power supply by actively adjusting a resonant frequency of a tank circuit; and

throttling the power applied to the tank circuit.

13. The method of claim 12 wherein said throttling includes throttling a phase to control a secondary amplitude.

14. The method of claim 12 wherein said throttling includes a phase delay.

15. A contactless power supply for transferring power to a secondary electrically coupled to an electrically powered load and separable from said contactless power supply, said contactless power supply comprising:

a tank circuit having a primary for transferring power to said secondary by an inductive coupling, said tank circuit having a resonant frequency, wherein said power is supplied to said electrically powered load electrically coupled to said secondary;

an inverter coupled to said tank circuit, said inverter applying power to said tank circuit at an operating frequency; and

control circuitry coupled to said inverter, said control circuitry adapted to actively adjust a resonant frequency of said tank circuit, said control circuitry further adapted to throttle phase.

16. The contactless power supply of claim 15, wherein said control circuitry includes a digital signal processor for controlling a delay to throttle phase.

17. The contactless power supply of claim 15, wherein said phase throttle affects a secondary amplitude.

18. The contactless power supply of claim 15 further comprising,

a sensor coupled to said tank circuit and adapted to measure operating parameters of said contactless power supply;

and

a control system including said circuitry and adapted to control said inverter for supplying power to said primary, said control system coupled to said sensor and adapted to continually monitor said operating parameters, wherein said control system continually monitors said operating parameters from said sensor.

19. The contactless power supply of claim 18, wherein said operating parameters include a current in said tank circuit and a phase offset between a current and a voltage.

20. The contactless power supply of claim 19, wherein said current is an inverter current and said voltage is an inverter voltage.